In order to find out the difference of production characteristics between single wells in Hancheng Mining Area,based on the gas-bearing property of main coal seams of Hancheng Mining Area,the geological control factors were discussed in the paper,such as coal rank,coal maceral,geologic structures,and hydrogeological conditions,which has influence on the gas-bearing property.The results showed that the gas-bearing property of main coal seams had two typical characteristics:on the one hand,the gas-bearing property of No.11 coal seam of Taiyuan Formation was better than that of No.3 and No.5 coal seam of Shanxi Formation,which was closely related with the depth of coal seam and the sedimentary environment;The gas saturation of each coal seam was 25％ ～ 94％,with an average value of 63％,with the burial depth increasing,the gas saturation of each coal seam varied little,but it showed an increasing trend in general.The reason was that the coal reservoir in this area was under pressure reservoir,and it had not reached the critical point of the difference of the adsorption behavior of different coal and rock.It was also found that with the increase of metamorphic degree of coal and rock and the increase of vitrinite contentin this block,gas content and adsorption all increased,which was considered to concrete manifestation of the geological effect of coalbed methane controlled by the two coalifications;The gas content of coal bed was obviously controlled by the structural conditions and hydrogeological conditions.%为了找出韩城矿区单井之间生产特征差异性的原因,基于该区主采煤层的含气性特征,从煤岩变质程度、显微煤岩组分、构造条件、水文地质条件等4个方面探讨了影响该区主煤层含气性的地质控制因素.结果表明:该区煤层含气性具有2个典型特征,太原组11号煤层含气性好于山西组3号煤层和5号煤层,这与煤层的埋藏深度和沉积环境有关;各煤层的含气饱和度为25％～94％,平均为63％,随埋深变化较小,但总体上呈现增大的趋势,分析原因该区煤储层为欠压储层,还没达到不同煤岩吸附性能差异的临界点.同时发现,随煤岩变质程度和镜质组含量的增高,煤岩含气量和吸附性均呈升高的变化,认为这是2次煤化作用对煤层气地质条件控制效应的具体体现;煤层含气量受构造条件和水文地质条件的控制非常明显.
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